The state’s environmental regulator has declared today an Ozone Action Day for the Dallas/Fort Worth region including Parker and Palo Pinto counties.
The designation means conditions are favorable for the formation of ground-level ozone, visible as smog, and residents with asthma, are pregnant or otherwise vulnerable to respiratory ailments are encouraged to avoid going outdoors during the hottest part of the day.
Residents also are asked to limit driving if possible during those hours and to avoid idling vehicles, such as at drive-through restaurants, doing laundry or mowing lawns.
Ground-level ozone is formed when volatile organic compounds, which occur naturally from trees and other sources, clash with nitrogen oxide from industrial smokestacks and traffic on warm and sunny days.
The Dallas/Fort Worth region is categorized as in non-attainment with the ozone standard set in the Clean Air Act, a designation responsible for strict annual auto inspection exhaust standards and the potential withholding of federal transportation funds, among other penalties.
In addition to the Metroplex and surrounding counties, the regions around El Paso and Houston also are designated as in non-attainment with the Act.